Cutaneous T-cell lymphomas (CTCL) are clonal lymphoproliferative diseases that usually originate from ^CD4+ T-cells of the skin. They represent a heterogeneous group of diseases and are classified in a special EORTC classification for cutaneous malignant lymphomas and in a REAL classification (Revised European-American Classification of Lymphoid Neoplasms). The decision as to which of the two classifications is preferable should be made on an individual basis. In principle, both classifications differentiate between B-cell and T-cell lymphomas.
The EORTC classification only considers primary cutaneous lymphomas, i.e. lymphomas that show no extracutaneous involvement at the time of diagnosis after a complete examination. In contrast, the REAL classification takes into account both nodal and extranodal lymphomas with secondary and primary skin involvement. In addition, the REAL classification is based on morphology, histochemistry and clinical aspects.
In our clinic, the EORTC classification is initially selected as part of the lymphoma consultation, as the individual primary cutaneous skin lymphomas are analysed in more detail.
The diagnosis is initially made by clinical examination with an extensive systemic examination, histological/immunohistological processing and finally a molecular biological examination technique for the detection of clonal T cells.
The multifocal appearance of the skin symptoms suggests that the clonal T cells circulate between the skin and blood. In fact, using these sensitive techniques (PCR), clonal T cells that are identical to those in the skin can also be detected in the peripheral blood in the majority of patients. Even in the early stages of cutaneous T-cell lymphomas, a T-cell clone is found in the blood in around 50 % of cases.
This sensitive PCR detection of distinct T-cell clones is part of the routine arsenal of the local lymphoma consultation.

The treatment of cutaneous T-cell lymphomas is carried out in a phase-adapted manner.
It is based on the use of PUVA, estracorporeal photopheresis, radiotherapy, interferon (IFN-alpha), retinoids, chemotherapeutic agents (BCNU, chlorambucil, methotrexate) and their combination as well as experimental therapeutic approaches. PUVA therapy corresponds to therapy with psoralen tablets two hours before UVA irradiation; if PUVA therapy is combined with retinoids, it is referred to as RE-PUVA.
If PUVA therapy is combined with interferon, it is referred to as IFN-PUVA.

Table 1 for the treatment of cutaneous T-cell lymphomas

The diagnosis and treatment of cutaneous malignant lymphomas has been carried out continuously for many years at the Department of Dermatology and Allergology at Ulm University Hospital. There is a database with more than 120 follow-up lymphoma patients.
Our clinic is a member of the EORTC group for cutaneous malignant lymphomas and is therefore up to date in the field of diagnostics, therapy and aftercare.